Jose L. G. Posted November 23, 2018 Share Posted November 23, 2018 Hi Danny. My ply brace has the grain in the correct direction. Also have to make a second one of each. Cheers. José Luis. Quote Link to comment Share on other sites More sharing options...
Martyn K Posted November 23, 2018 Share Posted November 23, 2018 My braces were correct as well DannyJust looking at your spar extension. When you cover the tip, the soar extension will be visible. To get the right profile you will also need to sand the top profile quite a lot. My extensions are hidden and finish at the inner edge of the tip. I think the underside treblers should really be 1/16 balsa but it's no big deal sanding them down. I suspect there may be 20 variants of Doing these tips 😂Edited By Martyn K on 23/11/2018 17:14:50 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 23, 2018 Author Share Posted November 23, 2018 Okay great Thanks for the feedback José Luis. Thanks Martyn the wings have not been sanded down yet, nor have the capping strips been added. A pet hate of mine is spars (and any structure) showing through the covering to the surface, so don't worry that will not be happening. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Martian Posted November 23, 2018 Share Posted November 23, 2018 Hi Danny I dont know whether you tracked down a source for carbon fibre tape , I got mine from here for a different project Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 23, 2018 Author Share Posted November 23, 2018 Thanks Martian, I will get some, and experiment Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 23, 2018 Author Share Posted November 23, 2018 Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 24, 2018 Author Share Posted November 24, 2018 Wing joining time. If you are joining the wings permanently the process is the same, except for the balsa blocks that go between the spars, bridging the centre section to the wing panel. I am doing that bit differently but you will see. The centre section is packed up on the spars by 1/8 front and rear. The wing spars are also propped up by 1/8 at the root. The wing tip is raised 47.6mm from the plan. However because the spars are propped by 1/8 wedges the tips need to be raised 47.6 + 3.175mm or a gnats nadger over 50mm.I found that 4 lego bricks placed in the bay just outboard of the strut bay works perfectly. I used 15 minute epoxy and clamps. The balsa blocks were in place until everything was clamped securely. Then the block removed before the epoxy had a chance to set. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 24, 2018 Author Share Posted November 24, 2018 I want the wings to seperate, there is no real need for this, as this isn't a big model really. However I want to re-create the gap between the wing panels, which is especially obvious on the top wing. I also want to practice doing this as I have a couple of models further down the line, on which I want to do something similar. I sanded sections of the original block spar joiners using a 1/4 permagrit rat tail file. This gave me a channel for my 1/4 OD carbon tube. The Tube is to be glued parallel tot the wing panel spars, and at the dihedral angle in the Centre section. This means there wont be as much tube inside the centre section as the wing, so the centre section spars are spruce. I then cut the dihedral brace along the centreline, and packed the tubing area with 30 minute epoxy and coloidal silica. I had added small hardwood dams at either end of the tube, to confine the epoxy. The coloidal silica looks like Micro balloons but it is a stiffener and makes a really hard epoxy fillet. The ply doubler is then attached to the spars and clamped until dry. This is repeated for the leading edge spar also. Cheers Danny Edited By Danny Fenton on 24/11/2018 16:35:28 Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted November 24, 2018 Share Posted November 24, 2018 Interesting stuff! Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 24, 2018 Author Share Posted November 24, 2018 The carbon tubes dont do much more than locate the wing roots. Until the flying/landing wires are fitted it will be fragile. But the individual wing panels will be easy to work on.CheersDanny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 24, 2018 Author Share Posted November 24, 2018 Well it seems to have worked okay. There are two tubes, the inner a tight fit in the outer. These are super glued together to keep them secure. The idea is to increase the wall thickness. The Carbon rod takes the load (hopefully). Cheers Danny Quote Link to comment Share on other sites More sharing options...
Martian Posted November 26, 2018 Share Posted November 26, 2018 Hi Danny nice progress super work ,any idea where you will place the fuselage servos ? Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 26, 2018 Author Share Posted November 26, 2018 Hiya, still hoping to put them just behind F1. I want EVERTHING as far forward as I can get themCheersDanny Quote Link to comment Share on other sites More sharing options...
Martian Posted November 26, 2018 Share Posted November 26, 2018 Thanks Danny that's what I'm aiming for providing i get the lipos forward of f1 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 27, 2018 Author Share Posted November 27, 2018 I am just joining the port wing to the centre section and thought i would show more detail on wing alignment for those that are unsure. The wing is layed over the plan to ensure the spars are the right length, and adjusted as need be. The wing is then propped up to 47mm and an engineers square is used to mark the dihedral angle on the spars, and these are sanded to match the centre section. The ply dihedral braces may also need shortening (they did on mine, and others have also commented) The centre section is placed accurately over the plan, and 1/8 scrap blocks fitted under the spars (make sure doublers for the other wing are flush with the spar) Then place 1/8 scrap blocks under the wing panel spars at the root. 3 lego blocks under the wing at the bay after the strut bay will lift the tip about the right amount. Use engineers squares to project upwards from the plan at the leading/trailing edges and tip, to ensure the wing is positioned accurately. The engineers square at the tip, marked at 50mm, helps to ensure the tip is at the right height and above the plan. The tip needs to be just 50.6mm off the board. The spars are then epoxied to the doubler attached to the centre section, and allignment treble checked. I use 15 min epoxy for this so I have time to adjust. Cheers Danny Edited By Danny Fenton on 27/11/2018 10:48:34 Edited By Danny Fenton on 27/11/2018 10:49:01 Quote Link to comment Share on other sites More sharing options...
Martyn K Posted November 27, 2018 Share Posted November 27, 2018 Those carbon tubes and rods will be more than adequate. I use the same method on my RC gliders and they get far more abuse than these models will get. The trick is to get the tubes supported down the full length so they don't buckle. I used balsa and then epoxy for any gap filling. When I took my Bubble Dancer F3J glider to the club night at the pub we actually tried to break the wing by bending it over our knees and failed miserably. Mined ewes - that was with 10mm carbon rods as joiners Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 27, 2018 Author Share Posted November 27, 2018 Hi Martyn, the square section tube fractured under test so I resorted to round section. As you say the tube has to be encased in epoxy/coloidal silica so that the tube cannot split. The carbon rod is not very thick on this and wouldn't work on its own, this model needs the flying wires. This channel was filled with epoxy/coloidal mix, then the ply doubler closing the top. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 27, 2018 Author Share Posted November 27, 2018 As I am splitting my wings once the spars are alligned, I remove the balsa spar joiners. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 27, 2018 Author Share Posted November 27, 2018 Once that is dry I cut 6cm of 5mm and 4mm carbon tube, slid one inside the other and wicked in thin CA Cut the balsa joiner in two, just to ease sanding the channel for the tube. glued the channels in between the spars, added hardwood dams at either end and filled the area with epoxy/coloidal slurry. This was then encased by the addition of the ply doubler. On to the front spar now. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Martin Fane Posted November 29, 2018 Share Posted November 29, 2018 Danny Excuse my ignorance but am I correct in thinking you get the joiner parts all assembled and epoxied up and when dry cut through the whole spar / brace assemblies at the centre section to outbosrd panel interface. Then insert a suiitable length of joiner rod. Cheers Martin Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 29, 2018 Author Share Posted November 29, 2018 Once the wing was dry the spar was sawn through where the wing panel meets the centre section and the ends tidied up. Next I added the root ribs, these had to be made up as sections from other surplus ribs as i had not drawn these specifically. Next the false leading edge was shaped to follow the shape of the spar, and some of the tip shaped. Then some 1/16 leading edge sheeting was added. Nearly forgot to add my riblets, easy enough with only the upper sheeting in place. Then all the capping strips were added to the ribs and riblets. Next will be spar webbing, then I can flip the wing and give it a good sanding. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 29, 2018 Author Share Posted November 29, 2018 Posted by Martin Fane on 29/11/2018 18:24:35: Danny Excuse my ignorance but am I correct in thinking you get the joiner parts all assembled and epoxied up and when dry cut through the whole spar / brace assemblies at the centre section to outbosrd panel interface. Then insert a suiitable length of joiner rod. Cheers Martin Yes Martin you are spot on. I think this is the best way to get it perfectly alligned, but not the only way Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted December 1, 2018 Author Share Posted December 1, 2018 Added all the forward spar webs on the rear face. The wing is much more rigid, so wont add the rear spar webbing. Flipped the wing and added the underside sheeting and cap strips Cheers Danny Quote Link to comment Share on other sites More sharing options...
Jose L. G. Posted December 2, 2018 Share Posted December 2, 2018 Hi Danny. In your last pic appears that you had shortened the trailing Edge of the wing. Are you planning something ? Cheers. José Luis Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted December 2, 2018 Author Share Posted December 2, 2018 Hiya this is the Nimrod, a chunk of the trailing edge is missing by the root CheersDanny Quote Link to comment Share on other sites More sharing options...
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